Einstein's E=mc² Proof (in 2 minutes)

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  • เผยแพร่เมื่อ 16 ม.ค. 2025

ความคิดเห็น • 58

  • @zhelyo_physics
    @zhelyo_physics  2 ปีที่แล้ว +6

    Most COMMON misconception: Topic of another video but the gravitational mass is unaffected by linear velocity, which is a VERY common misconception. Only how hard it is to "push" an object, i.e. it's inertia. Otherwise you get crazy predictions like accelerating a proton to close to the speed of light and it exerting near infinite gravitational force! : )

  • @zhelyo_physics
    @zhelyo_physics  2 ปีที่แล้ว +10

    For the coders out there btw: I coded the animations using Manim in Python, the software created by 3blue1brown. I am blown away by its potential for visualisations in physics!

  • @Zodiaczero2
    @Zodiaczero2 2 ปีที่แล้ว +6

    wow no calculus is needed!
    I love this derivation!

    • @zhelyo_physics
      @zhelyo_physics  2 ปีที่แล้ว +4

      I am always amazed how little calculus there is in SR! Probably a testament to the fact we are dealing with intertial frames of reference. Thanks for the comment!

    • @Zodiaczero2
      @Zodiaczero2 2 ปีที่แล้ว

      @@zhelyo_physics absolutely!

  • @thomasolson7447
    @thomasolson7447 ปีที่แล้ว +3

    There is an 'i' in momentum. E=mc^2 is hyperbolic.
    cos(arctan(i*y/x))=c/sqrt(x^2+y^2)
    γ(x,y)-> x/sqrt(x^2+y^2)
    γ(i*v, c)=1/sqrt(1-(v/c)^2)
    sin(arctan(i*v/c))=i*v/sqrt(c^2-v^2)
    p=mvγ/c=m*v*cos(arctan(i*v/c))=m*c*v/sqrt(c^2-v^2)
    the v in p has the 'i'
    i*v/sqrt(c^2-v^2)≠m*c*v/sqrt(c^2-v^2)
    There is also a limit to γ, it is sqrt(c^2-2). Anything greater than v=c-1/c is meaningless.
    cos(arctan(i*sqrt(c^2-2)/c))+sin(arctan(i*sqrt(c^2-2)/c))=c*sqrt(2)/2+i*c*sqrt(2)/2.
    This is 45 degrees. The function continues at -45 degrees, so anything greater than sqrt(c^2-2) and less than c is meaningless.
    @-45 degrees and moves to zero, the value @-45 degrees is c*sqrt(2)/2-i*c*sqrt(2)/2
    (c*sqrt(2)/2+i(c*sqrt(2)/2)+c*sqrt(2)/2-i(c*sqrt(2)/2))/2=c*sqrt(2)/2
    (c*sqrt(2)/2+i(c*sqrt(2)/2))(c*sqrt(2)/2-i(c*sqrt(2)/2))=c^2

    • @swagg6301
      @swagg6301 5 หลายเดือนก่อน

      Could you explain why the higher order terms are negligible and omitted?

  • @Zodiaczero2
    @Zodiaczero2 2 ปีที่แล้ว +2

    Hi ZPhysics, I love differential equations in physics, can you make more videos about them?

    • @zhelyo_physics
      @zhelyo_physics  2 ปีที่แล้ว +4

      For sure! Me too! 😀 have lots of things planned, stay tuned!

  • @tomtomspa
    @tomtomspa ปีที่แล้ว +1

    For someone who has the standard model lagrangian on his shirt, you should've known before making this video that mass is Lorentz invariant and as such there's no thing like relativistic mass. Mass is the same in every inertial frame and therefore a body at rest with mass m has the same mass m when moving near to the light speed.

    • @zhelyo_physics
      @zhelyo_physics  ปีที่แล้ว +2

      Completely agree, btw, I took extra care to call it inertia. In the case of the binomial expansion it is pretty useful to give the first term a name and the rest of the energy expansion a name. Thanks for the feedback!!

  • @Jihan-2007
    @Jihan-2007 6 หลายเดือนก่อน +1

    E= mc^2
    E=? M=? C =?
    What's the answer?😊

  • @zvast
    @zvast ปีที่แล้ว +1

    Why speed of light square?

    • @zhelyo_physics
      @zhelyo_physics  ปีที่แล้ว

      seems to come naturally out of the expansion, very interesting.

    • @joedeglman5862
      @joedeglman5862 7 หลายเดือนก่อน

      Momentum in the ether medium is an mv^2 function.
      It was actually derived, prior to Einstein plagiarizing it, from fluid dynamics.

    • @MOversteegen
      @MOversteegen 4 หลายเดือนก่อน

      It comes from momentum p = m*v.
      If two bodies with the same mass collide with each other elastically. The overall momentum will be Zero.
      A) Collision
      ---------->00 use the binomial expansion used in this vid. and you get E = mc^2
      So squaring c was already there during the deriving of the Lorenz factor 1/(1-v^2/c^2). In this case with the example I used with Pythagoras. But this is a simple example.

  • @abandz1132
    @abandz1132 2 ปีที่แล้ว +1

    Is there a easy or simple definition for inertia because it sometimes confuses me when out into other contexts

    • @zhelyo_physics
      @zhelyo_physics  2 ปีที่แล้ว +3

      yep! F=ma, m=inertial mass.
      This is your Newtonian mass and in relativity it is essentially your rest mass, m_0 in the video. Hope this helps!

    • @abandz1132
      @abandz1132 2 ปีที่แล้ว +1

      Thanks I get it now 🙏

  • @cincinnatibrutality0201
    @cincinnatibrutality0201 3 หลายเดือนก่อน

    Mc2=e ?

  • @madspetersen1708
    @madspetersen1708 ปีที่แล้ว +2

    There is no such thing as relativistic mass and rest mass, just mass.

  • @Exar-Kun-fake
    @Exar-Kun-fake 10 หลายเดือนก่อน

    What's the difference between ,,m0" and ,,m"

    • @zhelyo_physics
      @zhelyo_physics  10 หลายเดือนก่อน +1

      m0 is the rest mass and m is a term which changes the momentum as the speed changes. I call it inertia in the video I think.

    • @Exar-Kun-fake
      @Exar-Kun-fake 10 หลายเดือนก่อน +1

      ​​@@zhelyo_physicsThank you!
      I noticed something, in m= m0/sqrt(1-v^2/c^2
      m= m0×(1-v^2/c^2)^½ is wrong because its m0×(1-v^2/c^2)^-½ which I calculated (just for safe) and its actually in ^-½

  • @TommyRaines
    @TommyRaines 4 หลายเดือนก่อน +3

    Poor explanation accompanied by a ridiculously shouty delivery 😢

    • @zhelyo_physics
      @zhelyo_physics  4 หลายเดือนก่อน +1

      thank you for the feedback. It is genuinely useful to hear.

  • @jherbranson
    @jherbranson 8 หลายเดือนก่อน

    Thank you and 'subbed'. Great content!

    • @zhelyo_physics
      @zhelyo_physics  8 หลายเดือนก่อน

      thank you very much for the comment!

  • @BenB-yk7kd
    @BenB-yk7kd 8 หลายเดือนก่อน +1

    Not into geometry? Here's a very basic question that should give you pause. Why do you claim -6×-6 = 36 ? Or that 1/0 = i ? Because you're too proud to admit you just don't know and never will

    • @BenB-yk7kd
      @BenB-yk7kd 8 หลายเดือนก่อน

      Lol you fool it's the root of -1 that is i!

    • @BenB-yk7kd
      @BenB-yk7kd 8 หลายเดือนก่อน

      And E=mc^2 just prove it prove it in a lab

    • @BenB-yk7kd
      @BenB-yk7kd 8 หลายเดือนก่อน

      Its all bs

    • @BenB-yk7kd
      @BenB-yk7kd 8 หลายเดือนก่อน

      BTW those crazy reaches of logic were all made when the numbers weren't fitting the narrative just use letters. If they ask you how fast is electricity you just say a big number and we'll find a way to make it fit

    • @squarerootofscience1847
      @squarerootofscience1847 6 หลายเดือนก่อน

      What are you going on about???

  • @anamitrasaha5806
    @anamitrasaha5806 4 หลายเดือนก่อน

    Wonderful explanation,but idk if i am right but mc²=m0c²+m0v²/2 must be super close to E but not exactly,to me it seems that it would be true in partial relativity but in total relativity,that thing is super close but not exact,but wonderful explanation man,keep it up,such a complex concept explained so simply yet mathematicaly.😮😮

    • @zhelyo_physics
      @zhelyo_physics  4 หลายเดือนก่อน +1

      Very good question. You are correct..for small speeds, v. The idea is the first term does not depend on v, and each subsequent term will get bigger and bigger as v increases. Hope this helps!

  • @mylogify
    @mylogify 3 หลายเดือนก่อน

    It's not pronounced Einstein. It's like Einshtein, why people keep saying this?

  • @BenB-yk7kd
    @BenB-yk7kd 8 หลายเดือนก่อน

    How could man know the speed of light? Start there now tell me how he proved that this was any more than a pipe dream

  • @Yahya-t8j
    @Yahya-t8j 4 หลายเดือนก่อน +1

    Yo proved something with something came from it

    • @zhelyo_physics
      @zhelyo_physics  4 หลายเดือนก่อน

      Not really, the concept of the gamma factor is introduced first and then gradually length contraction and ideas of momentum. Hope this helps!

    • @Yahya-t8j
      @Yahya-t8j 4 หลายเดือนก่อน +1

      Oh ok now i know it thanks but the length contraction was one of main assumptions in relativity it was assumed to be parallel in direction of motion to be able to get gamma if we don't assume that we won't get the formula for time diluation also ​@zhelyo_physics

    • @zhelyo_physics
      @zhelyo_physics  4 หลายเดือนก่อน +1

      interesting point. Actually not. Time dilation and hence the gamma factor is a consequence of assuming Einstein's Postulates of Special Relativity. Once you have the gamma factor you can derive Length Contraction, The Lorentz Transformations etc.
      I have all the derivations here if you are interested: th-cam.com/video/nUymnmiIZo4/w-d-xo.htmlsi=jM6BevXfDeTlrUaz. Have a great day!

    • @Yahya-t8j
      @Yahya-t8j 4 หลายเดือนก่อน +1

      @@zhelyo_physics I don't mean that the formula was one of the main postulates I mean the assumption that length only contract in parallel direction of motion if he didn't assume this we won't use the train and light beam experiment to get gamma as the vertical length of train in its rest frame won't equal the one in the observer frame so we need to assume that first

  • @stewartstapleton649
    @stewartstapleton649 8 หลายเดือนก่อน

    Not need to be hard. Rubbish. You use the fact that m is related to m_0 via the Lorentz factor (go ahead and derive this) and then use the binominal expansion (again not easy for people not fluent in mathematics). I understood this derivation (and guessed it before the video started) but that's because I have a MSci in Mathematical Physics.

    • @zhelyo_physics
      @zhelyo_physics  8 หลายเดือนก่อน

      no problem, I appreciate the perspective a lot. My general audience is physics students who are familiar with the above. I am still amazed that most of relativity is based on geometry, algebra and some postulates which I find remarkable. Comparable to other theories that have changed our views of the universe, the mathematical simplicity of this one I find extremely elegant. Thank you for the comment.

  • @sunnyanandphylo8605
    @sunnyanandphylo8605 2 ปีที่แล้ว +1

    I want you solve one question of relativity I was unable to solve this problem
    Book: Robert Resnick Relativity
    Page: 48 , Problem:14 , Binary system
    Please sir my humble request with you , no one was help me 😥🥺

    • @zhelyo_physics
      @zhelyo_physics  2 ปีที่แล้ว +2

      Sounds interesting! Drop me a comment with the problem as I don't have the book handy at home.

    • @sunnyanandphylo8605
      @sunnyanandphylo8605 2 ปีที่แล้ว +1

      Problem containing figure too so it difficult to share 😅

    • @potato_nugget
      @potato_nugget 2 ปีที่แล้ว +2

      @@sunnyanandphylo8605 Take a picture and post it on imgur (or any image site) then post the link

    • @sunnyanandphylo8605
      @sunnyanandphylo8605 2 ปีที่แล้ว +1

      @@potato_nugget yeah 👍 thanks wait 👍

    • @sunnyanandphylo8605
      @sunnyanandphylo8605 2 ปีที่แล้ว +1

      @@zhelyo_physics drive.google.com/file/d/1N0xiPx-kuMurYyuQoi9B6ddJ4QJzuOGk/view?usp=drivesdk
      This is the problem